<!DOCTYPE html>
<title>CSS Test Reference</title>
<style>
  dialog {
    inset: 100px;
  }
  dialog::backdrop {
    background-color: green;
    inset: 100px;
  }
</style>
<dialog>Green backdrop with 100px inset</dialog>
<script>
  document.querySelector("dialog").showModal();
</script>
